UPDATE 9/20/17: After FOX 4 featured Antoine White's murder, several people came forward to identify his killer seen in surveillance video as John Edward Morgan, 19, who was already in jail for another homicide. He has now been charged with White's murder.

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This week, Dallas police need help to track down a murderer in a case that the lead detective says still "haunts him."

Ten years in the homicide unit, Detective Tim Stewart has put together plenty of books on murders.

“Everything involved in the case is in this book,” he said.

Antoine White was murdered on April 28 just two blocks from his grandmother's home.

“He would check on my grandmother and my father,” said Aaron White, Antoine’s brother. “They live right there in Glendale Oak Cliff.”

Antoine had been living in Austin with his brother but returned to Dallas to check on family.

In the early morning of April 28, Antoine went to Autry's Convenience Store on Lancaster with cash in hand.

“I think he was actually robbed or the guy that did this had some beef with him from the streets,” Stewart said. “He was basically laying halfway on the street, and the rest of his body was halfway off on the side.”

The detective is sure Antoine fought for his life.

“There were two baseball caps laying here beside him,” Stewart recalled. “One was his — we know from the video. And one belongs to the suspect.”

The suspect was caught on surveillance video outside the store before Antoine’s murder. Two things stand out and police hope they help them find him. First, his backpack was military-like with thick shoulder straps and a strap around the waist. He also has a distinct difference to his right forearm.

“On his right arm, it’s either a burn or some sort of a skin disease,” Stewart said. “I think it’s a problem that he has or scar. That if someone knows him, they're gonna know that that’s him when they see that.”

Stewart is pleading for the public’s help to put Antoine’s killer behind bars.

“What I need is someone to give me a call and tell me what this guy’s name is. That’s all I need,” the detective said. “They can remain anonymous. I just need a name. They can call me. They can call Crime Stoppers. However they want to do it, I just need this guy’s name.”

“They took him from his daughter, Amaya. He didn’t even get a chance to see his thirty-eighth birthday,” Aaron said. “They killed my brother a day before his birthday. It’s not right. It’s hurting, and we want some justice.”

Anyone who may know the suspect is urged to call (214) 671-3635. A reward is being offered.

Dallas police have a group of murders that are unsolved and growing old because leads have gone cold.

For several of the cold cases, police are hanging their hopes for an arrest on the public's eyes and surveillance video. They are now turning to FOX 4's Shaun Rabb to help ‘Trackdown' the criminals.